1. Field of the Invention
This invention generally relates to weighing systems, and more particularly to an electronic scale and a system and method which uses the electronic scale to compute postal and private carrier rates for letters, packages, parcels, and other items of mail.
2. Description of the Related Art
Even with E-mail and other forms of electronic data transfer which are so prevalent today, traditional mail, either through the U.S. Postal Service or by private carrier, remains the dominant form of information exchange. In order to successfully send an item through the mail, correct postage must, of course, be computed. To determine postage, a number of factors must be taken into consideration, not the least of which include the class, destination, and weight of the item being sent. At least three methods are currently in use for determining the weight of mail, and as will be apparent below all of them fall short of being optimum.
The traditional method of weighing mail involves using an analog scale. According to this method, a letter is weighed on the scale and postage is then determined by comparing the scale measurement to a rate table issued by a mail carrier. This method has proven to be inefficient, especially for businesses, because it is an entirely manual process. To mail a letter, for example, a secretary is often required to go to a mail room to access the scale and rate tables. In other instances, the scale is kept at the secretary""s desk, making a trip to the mail room unnecessary. Even under these circumstances, however, the process is inefficient because keeping the scale on the secretary""s desk reduces her usable work space. Either way, the traditional method of computing postage is inefficient.
An improved method of computing postage involves using an electronic, programmable postal meter. Electronic postal meters are highly favored by businesses because they essentially automate the mailing process. While meters of this type come in varying sizes, from small stand-alone units to full-size systems capable of weighing packages of varying weights and sizes, all have the same basic features: a keyboard for entering rate data into a meter memory, an electronic scale, and a processor for computing postage based on the stored rate data and weight measurements taken by the scale. U.S. Pat. Nos. 5,724,245, 5,615,120, 4,814,995, and D 305,103 disclose meters of this type.
In spite of their advantages, electronic postal meters have at least three drawbacks. First, postal meters cannot be bought but only rented for a fee. These rental fees contribute to operating expenses, and sometimes significantly depending upon the size of the renter.
Second, electronic postal meters require considerable maintenance because, one, the scales connected to the meters must be manually adjusted every time new postal rates are issued and, two, the meters must be periodically inspected, serviced, and replaced, often at additional expense to the renter.
Third, most electronic postal meters in use today are of a size which, in practical terms, are unsuitable for use on a worker""s desk. Consequently, postal meters are almost universally kept in mail rooms and thus have associated with them many of the inefficiencies attendant to analog scales.
A further improved method of computing postage borrows from the power of the personal computer. This method eliminates the need for electronic postal meters because the functions performed by the meter processor are replaced by a CPU running a postal computation program. Computer programs of this type, exemplified by U.S. Pat. No. 5,606,507 to Kara, are typically Windows-type programs which automatically compute postage based on weight measurements taken by an electronic scale connected to a communications port of the computer. Once postage has been computed, the program instructs a peripheral device to print an envelope or label bearing a stamp of appropriate value.
Use of a personal computer to compute postage represents a significant improvement in the art. Through the computer, a secretary can, for example, perform all mailing responsibilities at her desk, thereby streamlining the mailing process. Further, through a convenient and easily understandable graphic user interface, novices can in no time learn to use the postal program with a proficiency equal to that of trained personnel. Also, because postal programs can be purchased, they do not represent a continuing economic burden on the businesses which use them.
For all of their advantages, software-based mailing systems are not optimum because they are not fully integrated. Perhaps most significantly, while the processing functions of the electronic postal meter have been incorporated into the personal computer, its hardware components have not. This is exemplified by systems like Kara, discussed above, which still must use an electronic scale separate from the computer to obtain the weight measurements required for computing postage. Use of a separate scale is inefficient because, like an analog scale, it consumes desk space which could be put to more productive use.
A need therefore exists for a system for computing postal and carrier rates which is fully integrated so that desk space is not unnecessarily consumed and which therefore is more convenient and efficient compared with postage-computing systems presently in use.
It is one object of the present invention to provide a system for computing postage and/or private carrier rates which is more efficient than those presently in use.
It is another object of the present invention to achieve the above object by integrally forming an electronic scale into the housing of a computer keyboard, so that all elements for computing rates are conveniently and compactly located on a user""s desk, thereby streamlining the mailing process and increasing the work space available to an individual in a home or business environment.
It is another object of the present invention to provide a an electronic scale having an attachment means for either permanently or removably attaching the scale to virtually any surface, whether vertical or horizontal, flat or curved, smooth or rough, to thereby improve a worker""s usable space as well as his or her convenience of using the scale.
The foregoing and other objects of the invention are achieved by providing an electronic scale which, in a first embodiment, is built into the housing of a computer keyboard. The electronic scale includes a platform for supporting an item of mail such as a letter, and a weighing unit having at least one support arm for transferring the weight of the mail item from the platform to a load cell mounted within the keyboard housing. In operation, an item to be mailed is placed on the platform. The weight of the letter causes the support art to impinge against the load cell, and resulting weight measurement signals are output to a display unit and/or a processor to allow a postage computation to be performed. The load cell may be powered from electrical lines connected to the keyboard, or may be battery powered.
A second embodiment of the present invention includes substantially the same features as the first embodiment except that the platform is removably connected to allow different types of platforms and holders to be connected to the weighing unit.
A third embodiment of the present invention includes: a weighing platform; a housing containing a weighing unit and a force transducer; and a means for attaching the housing to a work surface. The weighing unit includes two support members having a first end connected to the platform and a second end mounted interior to the housing. The support members may be provided with springs to allow the platform to deflect against the force transducer during weighing. The attachment means may be of any conventional type for allowing the housing to either permanently or removably attach to a work surface to thereby maximize a worker""s usable work space.